Lever



NO v. 16, 1937. P. C TEMPLE 2,099,244

' LEVER Filed Sept. 2l, 1954 Y; 6 z 6 2 64- I *67 I L7 60 3432 /.9 l Il'5 6754 Il. Illllll lll' Z Z3 l 37 e/ .f ,A /4 J 1 l a9 /fl 7 3 8/ a 53'49 6] 2/ Z737" 5 if" '46 Zv 7 v 40 47 6/ 4L- d 73 4J PAUL C. l' 7MP4Eheated Nvv- 1e, 1931 t 'I sTArEsrATENT 2,099,244 j nur c. Temple, paginanl., assigner u A..w. Cash Company, Decatur, Ill.,'a corporation ofDelaware l Application september zi, 1934, serial Nn. *144,948 w 4claims. (ci. 'i4-41o) n Y This invention relates to levers, vand moreparticularly to a lever suitable for transmitting movement fromv anautomatic control' device. such as a pressure responsive diaphragm, to ailow controlling valve. This application is a continuation in part oi.'my prior application Serial No. 646,835, illed December 1K2, 1932, nowPatent No. 1,992,048, granted February 19, 1935. y

Ii the force transmitted by the lever in'an apparatus of this typematerially ,exceeds that necessary to eilect .the desired movement ofthe valve. there is danger of overloading some part of the mechanism andcausing serious damage thereto. The valve may be of the seating type, Iand if lt is'jammed too tightly against its seat one or both oi' theseparts will be injured, and the operation will be renderedunsatisfactory.

It is accordingly one 4object oi' the invention to provide a simple,inexpensive and compact lever which will yield upon application of anexcessive force thereto. It is a further object of the invention toprovide an improved and compact construction for a lever which willyield upon application of an excessive torce thereto in any direction.

With these and other objects in view, as will be apparent to thoseskilled in the art, the lnvention resides in the ycombination of partsset forth in the speciication and covered by the claims appended hereto.

Referring to the drawing illustrating one embodiment of the invention,'and in which like reference numerals indicate like parts,

. Fig. 1 is a vertical section through the center of an automaticcontroller;

Fig. 2 is an enlarged view of a portion of Fig. 1, showing the lever inits flexed position; and

Fig. 3 is a section on the line 3-3 of Fig. 1.

'I'he embodiment illustrated comprises a hollow valve body or caslngll)divided internally by suitable partitions into an inlet chamber Ii, an

A outlet or exhaust chamber i2, and two intermediate chambers I4 and I5.'I'he exhaust chamber is located between the intermediate chambers, andthe inlet chamber is U-shaped and arranged with its end portionsadjacent to the intermediate chambers. An inlet opening i6 leadsdlrectly into the inlet chamber I I, and an exhaust opening Il leadsdirectly from the exhaust chamber I2. Similar openings (not shown)communicate directly with the intermediate chambers I4 and II.

Inlet ports orpassages i9 and 2li connect the inlet chamber with theintermediate chambers Il and I5 respectively, and exhaust ports orpassages 2l and 22 connect'the exhaust chamber with the intermediatechambers I4 and i5 respectively. In the preferred construction theseports i9, 20, 2l and 22 are arranged in direct axial alignment.

5 The ow of iluid through the casing I0 is conlong enough to hold thevalves slightly om the 15 exhaust seats when the stem is in its centralor f neutral position. This is particularly desirable rwhenthe valvestem is arranged to be actuated by an automatic pressure responsivedevice, since it removes a large part of the unbalancedload sensitive.However, if the fluid to be controlled is a gas, such as compressed air,the valve'ports can be made much smaller and the unbalanced load willthereforebecome of little importance. In such a case the valve stem ispreferably made slightly shorter. so that both valves will close againstthe exhaust seats whenthe valve stem is in its neutral position. Thisprevents any loss of iuid to the exhaust so long as ,the valve stemremains in this position. It will be understood that the valve stem isnot fastened to the ball valves, but merely pushes against them. Henceany inaccuracy or misalignment which may occur in the actualconstruction will not prevent 35 the valves from seating tightly.

In order that my improved four-way valve mechanism may be convenientlymanufactured and assembled, I prefer to form the various inlet andexhaust portsin separate parts which are removably mounted in the.casing lll. As illustrated, the exhaust ports 2| and 22 are formed inflanged hollow cylindrical members 21 and 28 respectively which are heldrmly in position by means of plugs 29 and 30 screw-threaded to thecasing I0. The plugs 29 and 30 are arranged in direct axial alignmentwith the members 21 and 29. The inlet ports I 9 and 20 are formed inilanged cylindrical members 32 and 33 which are screw-threaded to theinterior bore of the members-2l and 28. The plugs 29 and 30 are recessedaxially as shown at 34 to clear the iianged ends of the inlet seatmembers 32 ,and 33, and radial openings 35 are provided to communicatewith the recesses so that the fluid 55 Thesevalve's are con- 10 on thevalves and `makes the controller ,more 2 0 ilow to the inlet ports willnot be obstructed. Radial openings 31 are provided in the exhaust seatmembers 21 and 28 to establish communication between the interior ofthese members and the adjacent intermediate chambers.

It will now be seen that if fluid is supplied under pressure to theinlet chamber Il, and the valve stem 25 is moved upwardly, valve 23 willclose the inlet port I 9. At the same time, the uid pressure will forcevalve 24 upwardly to close the exhaust port 22. Fluid can therefore owfrom the inlet chamber Il to the intermediate chamber I5, and iluid canalso flow from the intermediate chamber I4 to the exhaust chamber I2. Ifthe valve stem is moved downwardly to its other extreme position, theinlet chamber will be connected with the intermediate chamber I4, andthe intermediate chamber I will be connected with the exhaust chamber.

In the construction illustrated, the valve stem 25 is arranged to beactuated automatically by means of a fluid pressure responsive diaphragm39 which is connected to the valve stem by means of a lever 40 of therst class. This lever is pivotally supported by means of a smallflexible diaphragm 4I which serves both as a fulcrum for the lever andas one wall of the exhaust chamber I2. This diaphragm 4I is preferablyformed from a thin fiat plate of a suitable material, such as phosphorbronze, and it is clamped at its periphery between the valve casing I Iland a diaphragm casing 43, these parts being suitably fastened together.'I'he intermediate portion of the valve stem 25 is enlarged and providedwith a transverse opening 44 to receive the spherical end 45 of theshort arm oi' the lever 40. 'I'he other end 41l of the lever, which isalso preferably spherical, is positioned within a transverse opening 46(preferably rectangular in cross-section) formed in a blockV 49 which issecured to the central portion of a lower pressure plate 5I. 'I'hecentral portion of the main diaphragm 39 is clamped between the lowerpressure plate 5| and an upper pressure plate 52. these plates beingfastened together by a'central stud 53 threaded into the block 49 andprovided with a nut 54 at its upper end. The main diaphragm is clampedat its periphery between the diaphragm casing 43 and a flanged uppercover plate 56 which is fastened to the casing 43.

It will now be seen that the main diaphragm 39 divides the spaceenclosed by the casing 43 and the cover plate 56 into an upper chamber51 and a lower chamber 58. 'I'he cover plate 56 is provided with anopeningy 60 leading to the chamber 51,

and the casing 43 is provided with an opening 6I leading to the chamber58. These openings are shown screw-threaded for convenience inconnecting `pipes thereto. A controlling fluid pressure may be appliedto either or both of these chambers, f

In order to support the main diaphragm against the controlling fluidpressure, I have shown a coiled tension spring 63 arranged in a verticalposition above the center of the diaphragm with its lower end connectedto the stud 53. The upper end of the spring is fastened to a nut 64which is mounted on a vertical screw 65. This screw is rotatablysupported in a housing 61.which is fastened to the cover plate 56, andvwhich servesto enclose the spring. The upper end ofthe screw 65 extendsthrough a stufng box '68 at the top of the housing 61, so that the screwcan be rotated to move the nut 64 l.-vertically and thus vary thetension of the spring.

'I'he controlling uid pressure to which the seat. The joint will providethe main diaphragm is subjected may become large enough to cause anexcessive load on the valve seats or fulcrum diaphragm. In order toprevent such excessive loading, I form the valve operating lever 40 witha flexible joint which is normally held rigid by a yieldable device.

In thepreferred construction illustrated the short arm of the lever isprovided with an hexagonal portion forming a shoulder, and an externallyscrew-threaded stud 1I which extends through the fulcrum diaphragm 4I. Asmall annular gasket 12 surrounds the stud 1I between the shoulder 10and the diaphragm, and these parts are clamped rmly together by means ofa flanged member 14 threaded to the stud. A flanged member isscrew-threaded to the adjacent end of the long arm of the lever, and thetwo members 14 and 15 provide plane cooperating surfaces which areperpendicular to the axis of the lever. These surfaces are normally heldin contact by means of a coiled compression spring 'I6 surrounding themember 15. 'I'he spring 16 is supported by means of an annular cap orcollar 13 screw-threaded to a cylindrical shell 19 integral with theange 14. 'I'he shell 19 surrounds A the member 15 and the spring 16. Thecap 13 is provided with a central opening considerably larger than theportion o1' the lever extending therethrough, so that the cap willpermit a substantial lateral pivotal displacement of one part of thelever relative to the other.

In order to maintain the correct augment between the two parts of thelever, I provide them with intertting portions which are nevertheless soshaped as to allow the desired flexing when necessary. For this purposethe end of the stud 1.I is formed with a spherical projection 8| whichts closely within a centrally located cylindrical opening 62 in theflanged member 15.

The operation of the invention will now be apparent from the abovedisclosure. The diaphragm 36 moves in response to any change in theeifective pressure thereon, and these movements are transmitted throughthe lever 46 and valve stem to the ball valves 23 and 24. These valvescontrol the admission of uid from the inlet chamber II to theintermediate chambers I4 and I5, thus controlling the pressure in thesechambers. This pressure may be used to move a double-acting piston in apower cylinder (not shown). In case the eifective pressure on thediaphragm 39 materially exceeds that necessary to close either of theball valves, the joint in the lever 40 will ex against the pressure ofthe spring 16, one part of the lever tipping laterally relative to theother part, as shown in Fig. .2, thus allowing the diaphragm to continueits movement without causing excessive pressure betweenA the. valve andits desired protection irrespective of the direction in which theexcessive force is applied. Upon restoration of normal conditions, thespring 16 will expand and hold the flanged member 15 in contact with themember 14. The spherical projection 8| will prevent relative slidingmovement between the contacting surfaces of the two parts of the lever,thus avoiding the undesirable eiect which such movement would have uponthe adjustment oi' the controller. The construction is simple andinexpensive to manufacture, and it is so compact and self-contained thatit may be readily applied to any controller of th type havin! aValve-861511' ating lever.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. A lever formed in two parts located in substantial alignment andshaped to provide plane cooperating surfaces perpendicular to the axisof the lever, a coiled compression spring surrounding one part of thelever and tending to maintain said surfaces in contact, and supportingmeans for the spring carried by the other part of the lever and shapedto permit a substantial lateral tipping of one part of the leverrelative to the other, whereby the lever will yield upon application ofan excessive force thereto.

2. A lever formed in two parts, each part of the lever having a flangethereon, a coiled compression spring surrounding one part of the leverand tending to maintain the corresponding llange in contact with theother flange, and an annular cap carried by the said other flange andarranged to support the spring, the cap having a central opening throughwhich one of the lever parts extends and considerably larger than saidlever part, whereby one lever part may be laterally displaced pivotallyrelative to the other part through a substantial angle.

3. A lever formed in two parts located in substantial alignment andshaped to provide plane cooperating surfaces perpendicular to the axisof the lever, one of said parts having a recess therein and the otherpart having a projection positioned within the recess to preventrelative sliding movement between said surfaces while a1- lowing lateraltipping of one lever part relative to the other, and a coiledcompression spring surrounding one part of the lever and tending tomaintain said surfaces in contact, whereby the lever will yield uponapplication of an excessive force thereto.

4. A lever formed in two parts located in substantial alignment andshaped to provide plane cooperating surfaces perpendicular to the axisof the lever, one of said parts having a cylindrical recess therein andthe other part having .a spherical projection positioned within saidrecess, and a yieldable device tending to maintain the said surfaces incontact.

PAUL C. TEMPLE.

